This invention relates to an LIF connector having an LIF (low insertion force) mechanism by which a multi-pole connector, having many terminals, can be easily inserted into and withdrawn from a mating connector.
The term "connector", used in this specification of the present invention, means a connector including at least male terminals or female terminals, and a housing receiving these terminals therein, and the housing may be either separate from or integral with other member.
A multi-pole connector has a plurality of terminals, and therefore a large insertion/withdrawal force is required for inserting and withdrawing the connector relative to a mating connector, and it has been rather difficult to effect the insertion and withdrawal of the connector. In view of the difficulty of insertion and withdrawal of such a multi-pole connector, there have now been proposed various connectors (LIF connectors) having an LIF mechanism.
A representative example of such conventional LIF connectors is one in which a connector is inserted and withdrawn by operating a slider.
One such conventional slider-type LIF connector is proposed in Japanese Patent Unexamined Publication No. Hei. 6-215827. The LIF connector, disclosed in Japanese Patent Unexamined Publication No. Hei. 6-215827 will be described with reference to FIGS. 1 to 6.
FIG. 1 shows a first connector (housing) of the LIF connector, and FIG. 1(a) is a plan view, and FIG. 1(b) is a view as seen along the line D--D of FIG. 1(a). FIG. 2 shows a second connector (housing) of the LIF connector, and FIG. 2(a) is a plan view, and FIG. 2(b) is a cross-sectional view taken along the line E--E of FIG. 2(a), and FIG. 2(c) is a front-elevational view. FIG. 3 shows a slider of the LIF connector, and FIG. 3(a) is a plan view, FIG. 3(b) is a cross-sectional view taken along the line F--F of FIG. 3(a), and FIG. 3(c) is a front-elevational view. FIGS. 4, 5 and 6 are view explanatory of the insertion/withdrawal operation of the LIF connector.
In FIG. 1, the first connector 110 of the LIF connector includes a box-shaped body having an open top, and many terminals (not shown) are provided at an inner bottom surface thereof.
As shown in FIG. 1(a), a retaining recess 111 and guide grooves 112 and 112 are formed in each of opposed longitudinal walls 110a and 110a of the first connector 110.
In FIGS. 1(a) and 1(b), guides 113 and 113 for respectively guiding rails 133 and 133 of the slider 130 are formed respectively in inner surfaces of the side walls 110a and 110a at lower ends thereof.
As shown in FIG. 1(b), insertion holes 114 and 114 for inserting the slider 130 into the first connector 110 are formed in an end wall 110b of the first connector 110, and the insertion holes 114 and 114 communicate with the guides 113 and 113, respectively.
In FIG. 2, the second connector 120 of the LIF connector includes a rectangular box-like body, and many terminals (not shown) are provided at a bottom of the box-like body.
Guide projections 121 and 121 are formed on each of opposed longitudinal walls 120a and 120a of the second connector 120, and a fixing recess 122 is formed in a central portion of each of the walls 120a and 120a.
In FIG. 3, the slider 130 of the LIF connector includes a pair of plate-like arms 130a and 130a, and two slanting cam grooves 131 and 131 are formed in each of the plate-like arms 130a and 130a. A lance 132 is provided at a central portion of each arm 130a, and the lance 132 comprises a resilient plate 132a, and an engagement projection 132b formed on a distal end of the resilient plate 132a.
The rails 133 and 133 are formed respectively on the plate-like arms 130a and 130a, and extend respectively along lower edges thereof.
The insertion/withdrawal operation of the conventional LIF connector, having the above construction, will now be described with reference to FIGS. 4, 5 and 6.
In FIG. 4, first, the two arms 130a and 130a of the slider 130 are passed respectively through the insertion holes 114 and 114 in the first connector 110. As a result, the resilient plates 132a of the lances 132, provided respectively at the arm 130a, are engaged respectively in the retaining recesses 111 formed respectively in the walls 110a of the first connector 110, so that the slider 130 is positioned relative to the first connector 110.
In this retained condition, the guide grooves 112 (see FIG. 1) in the first connector 110 are disposed respectively in registry with inlets of the cam grooves 131 in the slider 130. In this condition, when the guide projections 121 of the second connector 120 are introduced respectively into the guide grooves 112 in the first connector 110, the guide projections 121 are guided respectively into the cam grooves 131 in the slider 130, so that the second connector 120 is set on the slider 130.
Then, as shown in FIG. 5, the slider 130 is pushed into the first connector 110. As a result, the engagement between each lance 132 and the associated retaining recess 111 is released, and the second connector 120 descends along the cam grooves 131, and the second connector 120 is completely inserted into the first connector 110 as shown in FIG. 6. At this time, the engagement projections 132b of the lances 132 are engaged respectively in the fixing recesses L22 in the second connector 120, thereby fixing the second connector 120 in this fixed condition.
As a result, the terminals in the first connector 110 are connected respectively to the terminals in the second connector 120.
As described above, the purpose of the LIF connector is to reduce a force (insertion/withdrawal force) required for inserting and withdrawing the connector, having many terminals, relative to the mating connector having many terminals, and the LIP connector has the LIF mechanism as means for reducing such insertion/withdrawal force.
In the above conventional LIP connector, however, the lances 132 are provided at the slider 130, and the slider 130 is positioned relative to the first connector 110 through these lances. Therefore, when pushing or pulling the slider 130 so as to insert or withdraw the second connector 120 relative to the first connector 110, the lances 132 of the sliding slider 130 are in press-contact with the opposed walls 120a of the second connector 120, respectively, and therefore an extra force is required for pushing and pulling the slider 130.
Therefore, in the conventional LIF connector, the insertion/withdrawal force, required for inserting and withdrawing the connector, could not be sufficiently reduced.
And besides, since the lances 132 are in press-contact with the opposed walls 120a of the second connector 120, respectively, during the sliding movement of the slider 130, the engagement projections 132b of the lances 132 are worn, or the resilient plates 132a are deformed when the slider 130 is repeatedly inserted and withdrawn.